Legend to Figure 2.

Panel A-shows the subdivisions of the prefrontal cortex. The prefrontal cortex was defined as the part of the cortex lying anterior to a coronal plane intersecting the most anterior point of the genu of the corpus callosum. The prefrontal cortex was then subdivided by three axial planes parallel to a line passing through the anterior and posterior commissure. Each axial plane was determined at the same location for each participant after fitting a proportional (Talairach) grid system to the normalized brain. The prefrontal percolation yielded four prefrontal subregions: D = dorsal, MS = middle-superior, MI = middle-inferior, VA = ventral-anterior.

Panel B- The bending angle of the corpus callosum is the angle created by lines connecting the most anterior and posterior points of the corpus callosum with the midline of the corpus callosum.